The crime of assault varies from state to state (and under federal law), but is generally defined as intentionally putting another person in reasonable apprehension or fear of an imminent (immediate) harmful or offensive contact. The crime of assault may be committed even if there is no physical contact, as the criminal physical contact constitutes the separate crime of battery.

The crime of assault with a deadly weapon (also known as aggravated assault) occurs when someone uses a deadly weapon (gun, knife, club, tire iron, brass knuckles, etc.) during an assault.

In Washington State, assault is codified under RCW 9A.36 and is categorized into four degrees, with varying levels of severity. First-degree assault (RCW 9A.36.011) is the most serious, involving intentional infliction of great bodily harm, and can include assault with a deadly weapon. Second-degree assault (RCW 9A.36.021) also covers assaults with a deadly weapon and can involve substantial bodily harm or assault on certain public servants. Third-degree assault (RCW 9A.36.031) includes assaults against certain protected individuals, such as bus drivers or law enforcement officers, and may involve bodily harm. Fourth-degree assault (RCW 9A.36.041) is a gross misdemeanor and covers situations where the fear of harm or offensive contact is created, even without physical contact. Assault with a deadly weapon is typically prosecuted under first or second-degree assault, depending on the circumstances, and is considered a felony, which can result in significant penalties including imprisonment and fines.